Let’s say I want to calculate the velocity of a free falling body in vacuum. I want to do this in dependence of gravitational constant and time or distance and time with a fixed gravitational constant. That would be either one of velocity(g, t) = g*t velocity(d, t) = 9.81*sqrt(2*d/9.81) If I do t…

As a side note, sqrt(2*d/9.81) is the time a free falling body takes to travel a distance d. I’m afraid you have to explicitly access the field of your types where you store the value velocity(dist::Distance, t) = dist.d / t if you want to avoid overloading the needed methods. Which can be automa…

Yeah, I missed the g in the 2nd formula, thanks for pointing out, I corrected it. And you are right about the units of course. Velocity was only an example, in reality I need electric field, chemical potential, particle density etc. I had a look at Unitful.jl in the past and thought it only deals w…

Great! I didn’t know about AbstractNumbers.jl. Nice one!

Just played around a bit, the example on the github landing page is not working, there’s also a pull request to correct it. Looking in the test folder shows it should be something like struct MyReal{T<:Real} <: AbstractNumbers.AbstractReal{T} real::T end AbstractNumbers.number(x::MyReal) = x.re…

Replace x^2 in the definition of foo by x*x and the difference in performance disappears… Why? Because for ordinary floats, the compiler takes the opportunity to inline the call to pow as a straightforward multiplication, while it isn’t “smart enough” to figure it out for MyReal. What you are seeing…

Interesting. I can confirm the difference goes away. Thanks for the effort to figure this out! So depending on the package used with an AbstractNumer, there could be a performance loss because the compiler is “not smart enough”. I guess there could be quite a few cases where compiler optimisation d…

Dispatch on physical quantity or creating distinct types that behave like a float

General Usage

Eben60 September 22, 2023, 11:08am 6

I’m not sure I exactly understood you needs, but did you check DynamicQuantities.jl ?

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Dispatch on physical quantity or creating distinct types that behave like a float

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